This is a 5 week crossover design bioequivalence study to compare the Abbott cyclosporine to Neoral cyclosporine. 50 patients will undergo an open-label, pharmacokinetic and safety, conversion study that consists of a screening period; Period I (two weeks of dosing with BID Neoral); Period II (two weeks of dosing with BID Abbott cyclosporine); and Period III (one week of dosing with BID Neoral). Pharmacokinetic parameters of cyclosporine will be determined during 12 hour pharmacokinetic profile testing, including Cmax, Tmax, Ctrough, AUC, Cavg and CL/F. Cyclosporine trough levels will be evaluated between 12-hour PK profile visit days. The safety and pharmacokinetics of Abbot cyclosporine will be compared to Neoral cyclosporine.